This paper presents an Early Warning and Response System (eWAR) system
capable of preventing casualties and mass hysteria in the event of a possible
chemical release, be it criminal or accidental (in the case of an industrial spill).
Experiments are conducted on a lab-scale set-up which uses a wireless computer
interface to monitor important ventilation parameters such as air-velocity,
humidity, pressure, temperature and their influence on in-duct levels of Volatile
Organic Compounds (VOCs) and airborne contaminants. This system is
designed to reduce the severity of various airborne contaminants, including some
toxic agents, only when concentration of contaminants, regardless of type,
generate some abnormal pulses as compared with the average day-to-day normal
pulses of indoor and outdoor air. This capability of the system to be activated
and deactivated avoids the additional energy and maintenance costs associated
with continuous filtration, the frequent regeneration of filter media as well as the
cost of additional air handling units to compensate for pressure drops caused by
filters.
Preliminary results have been obtained using various chemicals and different
types of activated carbons (as filters); they show that the in-duct concentration
can in fact be controlled and significantly reduce the severity of some release
scenarios.
Keywords: HVAC, activated carbon, building protection, early warning.